On the Mexican Boundary Survey, a few fragments of fossils were found in the superficial detritus, near El Paso (longitude 106°), which indicated the existence of Silurian rocks in that vicinity; but none appear to have been found in place. Professor Hall remarks that "the specimens referable to strata of this age (Devonian and Silurian) are few, and they are in such condition as to give little satisfactory information regarding the rocks in place." The specimens obtained are figured in the Mexican Boundary Report, but not described, nor is their locality accurately stated.

Dr. Newberry, in his Report on the Geology of the Colorado river region, refers the lower portion of the strata exposed in the grand cañons of that river to the Devonian and Silurian series; but as no recognizable fossils were discovered by the Ives expedition from any rocks lower than the Carboniferous, this reference can only be taken as expressing a conviction based on lithological characters and stratigraphical considerations.

In view of the facts above cited, it will be seen at once how interesting this discovery is of undoubted Silurian rocks west of the Rocky mountains; and the more so, since we have in this remote region a recurrence of conditions and forms of animal life so closely allied to those with which we are familiar in the states east of the Mississippi. It is a very remarkable fact that these rocks have not been discovered in the Rocky mountains; and should farther explorations fail to reveal their presence, it will throw a new light on the history of the physical development of the central and western portions of this continent. Taking into view what has now been communicated, and what was stated in my previous paper in regard to the existence of the older stratified rocks in the Silver Peak District, it will appear that Dr. Newberry's generalizations were, in all probability, correct, and that we may expect to find in southern and southwestern Nevada the outcropping fossiliferous edges of the strata underlying the Carboniferous of the great Arizona or Colorado plateau, and that they will be proved to occupy an extensive area, and to yield a profusion of organic remains.

Among the specimens collected by Mr. Blatchley, as also by Mr. Clayton, Mr. Melville Attwood, and Dr. C. L. Anderson, and now at our office, there is a considerable number which demonstrate the existence of an extensive freshwater Tertiary deposit in Nevada. This formation, which belongs to a very late Tertiary epoch, evidently occupies a considerable area, as our specimens come from localities hundreds of miles distant from each other. The existence of any marine formation more recent than the Jurassic, in Nevada, has not yet been proved; but, as Mr. Gabb obtained evidence, in 1864, of the occurrence of rocks of Cretaceous age on Crooked river, in Oregon, east of the Cascade Range, it is possible that this member of the series may yet be discovered in Nevada.

All the fossils referred to in this and my previous communication on the geology of Nevada, will receive, in due time, thorough investigation at the hands of Messrs. Meek and Gabb, or other competent paleontologists; and we expect that our collections from that state will be largely increased during the present year.-Proc. California Acad. Nat. Sci., iii, 307.

AM. JOUR. SCI.—Second Series, VOL. XLIII, No. 128.—MARCH, 1867.

10. Eozoön.-At a meeting of the Natural History Society of Montreal in January last, Dr. Dawson exhibited a photograph of a remarkable specimen of Eozoon Canadense, found the past summer in the Laurentian limestone of Tudor, Canada West, by Mr. Vennor, of the Canadian Geological Survey, and which had been examined and described for Sir W. E. Logan by Dr. Dawson. The rocks at Tudor and its vicinity, which, according to the observations of Mr. Vennor are Lower Laurentian, have experienced less metamorphism than is usual in formations of that age, and this peculiarity gives especial interest to the present specimen, which is contained in a rock scarcely altered and in a condition not essentially different from that of ordinary Silurian fossils.

The matrix is a coarse laminated limestone of a dark color, and containing much sand and finely comminuted carbonaceous matter. The fossil itself is of a flattened clavate form, about six and a half inches in length, and with the septa of its chambers perfectly preserved, exhibiting on one side a well defined marginal wall produced by coalescence of the septa, and apparently traversed by small orifices. Under the microscope the minute structures of Eozoon Canadense can be detected, though less distinctly perceived than in some of the specimens mineralized by serpentine. In some of the chambers there are small amorphous bodies containing pointed siliceous spicules, which seem to be the remains of sponges that have established themselves in the cells after the animal matter of Eozoön had disappeared.

The importance of this specimen was pointed out as establishing the conclusions previously arrived at from the study of the remains of Eozoön included in the serpentinous limestones, and as overthrowing the objections raised in some quarters to the organic origin of Eozoön. The specimen will be taken to England by Sir W. E. Logan, and full details of its characters will be communicated to the Geological Society, along with some other recent discoveries tending to the establishment of a second species of Eozoon.-Montreal Guzette, Jan. 29, 1867.

11. On Fossils in the Auriferous rocks of California; by W. P. BLAKE, (from a notice of the meeting of the California Academy, Aug. 20, 1866.) -Prof. Blake read a paper upon a "New Locality of Fossils in the Goldbearing Rocks of California," and exhibited specimens of Ammonites from a cut on the line of the Central Pacific Railroad, near Colfax. Although the specimen exhibited was quite perfect, it was not sufficiently so to enable the septæ to be seen. Prof. Blake remarked that these fossils were undoubtedly of the secondary period, and that they were apparently specifically identical with those from the American river, in the same vicinity, of which he had sent photographs to Mr. Meek, in 1863, and afterwards noticed the same at a meeting of the Academy in September, 1864; he also thought them identical with the species found at Bear Valley, Mariposa county. Prof. Blake also exhibited the tooth of an extinct elephant, a molar, found in the auriferous gravel near Michigan Bluffs; also, shark's teeth and other marine remains from Tulare valley; these remains were found by him at an elevation of at least twelve hundred feet above the sea, and probably belong to the Post-pliocene period.

66

Prof. Blake alluded to a Quarry of Gold-bearing rock" in Placer county, known as the Banker or Whisky Hill mine, where no regular

quartz vein exists, and the rock of the hill is profitably worked; some forty tons per diem are crushed, yielding from two to twenty dollars per ton-averaging from five to six dollars per ton.

12. On the Crystalline form of Pachnolite; by A. DESCLOIZEAUX. (From a letter to J. D. Dana, dated Dec. 6, 1866.)-Pachnolite is not quadratic as has been stated. Its crystals are much less simple. They belong to the monometric system, and appear to me to be always macled, in the same manner as are those of amphibole. As only a single summit is visible, the crystals being retained in the gangue by the opposite one, it seems as if we were dealing with a right rhombic prism. The four faces of the terminal octahedron are actually of the same kind, and belong to a positive hemi-octahedron, b. The crystals therefore appear as in the annexed figure, the axis of revolution being normal to the plane bisecting the acute angle of the fundamental prism. We may admit as a mean

m on m in front,

m on w lateral,

bon b (planes in figure) adjacent,

bon to adjacent,

Calculated.

m

Observed.

98° 40'

81 43 macle.

108 15

94 13 macle.

The plane of the optic axes is perpendicular to the plane of symmetry, and makes an angle of about 10° to 15° with a normal to the edge

m

m

and an angle of about 23° 15′ to 18° 15' with a normal to the edge One of the bisectrices is normal to the plane of symmetry; the other m by makes with the edges and the same angles as the plane of the bb

m

axes: but I have not yet been able to ascertain which of these is the bisectrix of the acute angle of the axes. The former is negative. As it has been impossible to cut a single thin plate normal to the bisectrices, it has not been possible to study the dispersion of the optic axes. The .crystals rest upon small, translucent, crystalline lamina, which appear to possess different optical properties. Is this mineral arksutite? These laminæ appear to make a transition stage between cryolite and pachnolite,

III. BOTANY.

1. Salices Europace; recensuit et descripsit Dr. FRIDERICUS WIMMER. Breslau, 1866. pp. 286, 8vo.-While awaiting the appearance of the general elaboration of the order, contributed by Dr. Andersson to the Prodromus, and of the Icones Salicum he has also prepared, we receive this beautiful volume, in which Dr. Wimmer, restricting his attention to the European Willows, has revised these with much detail and evidently with very great care. The work is written throughout in Latin. There is a full account of the literature of the subject, of the structure and morphology, and of the various systematic arrangements of the species which different authors have proposed. Dr. Wimmer himself arranges the Willows of Europe under eleven tersely characterized tribes, each comprising from one to six species. He admits only 31 to the rank of genuine species, reducing a great number to mere synonyms, and having well characterized these in the first half of his volume, he devotes the rest to Salices hybrida. These hybrids, 57 in number, and chiefly named according to their parentage, are disposed under fourteen sections, and their synonymy is fully indicated. The whole work gives the impression of being thoroughly reliable and excellent.

A. G.

2. Le Specie dei Cotoni descritte da FILIPPO PARLATORE. Florence, 1866.-Professor Parlatore's essay upon the long-vexed question of the species of Cotton was called forth by a Royal Italian Commission, and is dedicated to its President, Devincenzi. The letter-press, of 64 pages, 4to, is divided into a general history of cotton-plants, in Italian; and the description of the species, with the characters and full synonymy, are in Latin, but the farther details in Italian. He describes seven species (besides referring to as many doubtful ones): G. arboreum, or Tree Cotton; G. herbaceum, the common herbaceous Cotton; G. Barbadense, or Sea-Island Cotton; G. religiosum, or Peruvian Cotton; G. hirsutum, or Siamese Cotton; G. Taitense, as a new species, from Tahiti, which had been long variously confounded with others; and G. Sandvicense, also as a new species from the Sandwich Islands; but this has already been published by Dr. Seemann, under Nuttall's name of G. tomentosum. These species are all illustrated in a separate atlas of six plates, in elephant folio, beautifully exhibiting them in specimens of the natural size, in good lithography, all but the last two printed in colors. Our copy of this fine work is presented by the President of the Royal Commission, through the author.

Coniferæ, &c.-It is well known that Prof. Parlatore has elaborated the Conifera for the Prodromus. We have from him his study of the organography of the flower and fruit of this order, a memoir, contributed to the Annals of the Museum of Natural History at Florence, written in Italian; in quarto, with three folio plates, filled with structural details. Botanists are aware that he does not adopt the view that they are gymnospermous. We may soon expect, in the Prodromus, the full presentation of this view.

A separate little sheet contains characters, given in advance, of a few new Conifera: among them a Larch of N.W. America, Larix Lyallii, remarkable for a cobwebby woolliness of the young shoots and leaf-buds,

the scales of the latter with a fringed margin. We have from the same author his

Considérations sur le Méthode Naturelle en Botanique. 8vo pamph. Florence, 1863.-A good historical view of the development of the natural method, with some pertinent illustrations of the obvious importance in all the divisions, from highest to lowest, of looking to types and the ensemble of characters rather than resting upon single points,-in other words, of carrying the spirit of the natural rather than of artificial systems throughout the whole domain of botany.

A. G.

3. Tree-labels for the Arboretum.--Mr. J. H. Creighton, of Chilicothe, Ohio, who is forming, with rare and thoughtful generosity, an extensive arboretum for a college in Ohio, has contrived a plan of permanent label for the trees, which is worthy of general adoption in public grounds and parks. The label is of cast iron; and it exhibits in capital letters, in bold relief, the scientific and the popular name of the tree. Having the pattern and a stock of letters prepared for his own use, Mr. Creighton offers to cast, at a low rate, any number of labels, with any desired name.

A. G.

4. Ozone produced by Plants.-Professor Daubeny of Oxford has contributed to the Journal of the Chemical Society, for January last, an interesting article, giving the details of a series of careful experiments, which go to prove that green foliage, in assimilating carbonic acid, water, &c., liberates a part of the oxygen in the form of ozone. After his experiments were made, Dr. Daubeny found that Kosmann of Strasburg had reached the same conclusion, but through less refined experiments. Referring to the first paper he ever communicated to a scientific society, that published in the Philosophical Transactions for 1834, on the evolution of oxygen gas by plants in the day-time, Dr. Daubeny concludes: "Should I now have established to the satisfaction of the scientific world, that these same green parts of plants, at the very time they are emitting oxygen, convert a portion of it into ozone, I might hope that these researches of my later years will serve appropriately to wind up those undertaken in my younger ones, by showing that vegetable life acts as the appointed instrument for counteracting the injurious effects of the animal creation upon the air we breathe, not merely by restoring to it the oxygen which the latter had consumed, but also by removing, through the agency of the ozone it generates, those noxious effluvia which are engendered by the various processes of putrefaction and decay,"-engendered, we may add, as much by decaying vegetable as by animal matter.

A, G.

5. Morphology of Stamens, and use of Abortive Organs. In a recent number of the Gardeners' Chronicle, the editor, in giving a full account of Dombeya angulata,—a rare plant, which has just flowered at Kew,-describes as follows the morphology of the stamens, and the remarkable assistance which the staminodia, or barren stamens, seem to render as go-betweens, carrying pollen from the efficient stamens to the stigmas.

"The stamens in this plant, as in all the Malvales, may be looked upon as compound while the ordinary stamen corresponds to a simple leaf, the groups of stamens in the Mallows and allied orders may be regarded as the equivalents of compound leaves, united together at their bases.